Church History Series • Lesson 7 • Noll Turning Point 2

The Council of Nicaea (AD 325)

Constantine summons the bishops, the Son’s divinity is written into stone, and the church meets the empire for the first time • AD 312–381

By PS-Church • Following Mark A. Noll, Turning Points, ch. 2

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Where this fits: Lesson 7 of the Pleasant Springs Church History series — Noll’s second turning point. The theological vocabulary forged in Lesson 6 (Tertullian’s Trinitas, Origen’s Logos) is about to be hammered on an anvil no earlier generation had available: a Christian emperor. See the full Series Timeline.

WHY THIS LESSON MATTERS

In the summer of AD 325, somewhere between 250 and 318 bishops from across the Roman Empire travelled to the imperial palace at Nicaea — a small resort town on the Turkish side of the Sea of Marmara — at the personal expense of the Emperor Constantine. Some had arrived on crutches. Many carried visible scars from the Decian persecution and the Great Persecution of Diocletian. One of them, Paphnutius of Egypt, had only one eye; Constantine is said to have kissed the empty socket.

Twelve years before, the idea that Christian bishops would sit at an emperor’s table would have been a hallucination. Twelve years later, they did. In about eight weeks these men — many of them speaking at the first non-provincial gathering of their lives — produced the first ecumenical creed of the church, a document every major branch of Christianity still recites. They did it because they were forced to. A presbyter of Alexandria named Arius had begun teaching that the Son of God was the Father’s first and highest creation — not co-eternal with him. The question seemed technical. It was not. It was whether the one who saved us on the cross was God or was not.

This lesson tells how the crisis arose, what the church actually said at Nicaea, who fought the next fifty years to make the Council stick, and what Mark Noll means when he calls this the moment of “Realities of Empire.”

Greek NT (John 1:1): Ἐν ἀρχῇ ἦν ὁ λόγος, καὶ ὁ λόγος ἦν πρὸς τὸν θεόν, καὶ θεὸς ἦν ὁ λόγος. John 1:1 (ESV): “In the beginning was the Word, and the Word was with God, and the Word was God.”

PART 1 — THE WORLD CONSTANTINE MADE (AD 312–325)

For three centuries Christianity had been a religion that could kill you. By 324 it had become a religion the emperor was quietly favoring. Four moments produced the shift.

• AD 303 — The Great Persecution. Diocletian’s edict ordered the destruction of churches, the burning of Scriptures, and the execution of clergy who would not sacrifice. It was the most systematic persecution the church had yet faced, and its scars shaped the bishops who gathered at Nicaea a generation later.

• AD 312 — The Battle of the Milvian Bridge. The Western general Constantine marched on Rome against his rival Maxentius. Both Eusebius of Caesarea and Lactantius describe a vision — Eusebius says a cross of light appeared in the afternoon sky with the Greek words τούτῳ νίκα (“by this, conquer”). Constantine ordered the Chi-Rho painted on his soldiers’ shields, won the battle, and became master of the Western empire.

• AD 313 — The Edict of Milan. Constantine and his Eastern co-emperor Licinius issued a joint rescript guaranteeing religious freedom across the empire and the restoration of Christian property confiscated under Diocletian. It was not, technically, the “establishment” of Christianity — it was toleration. But after three centuries of intermittent killing, toleration was revolutionary.

• AD 324 — Constantine defeats Licinius. Now sole emperor of a reunited empire, Constantine immediately began to favor Christianity openly: restoring confiscated property, building basilicas (Old St. Peter’s in Rome, the Church of the Holy Sepulchre in Jerusalem), exempting clergy from civic duties, and legally recognizing Sunday as a day of rest in 321.

Noll’s title for this chapter — Realities of Empire — points to the double-edged character of the change. After 313 the church would never again be purely a persecuted minority. It would also never again be purely free of imperial entanglement. Both sides of that trade-off are already visible at Nicaea in 325.

PART 2 — ARIUS & THE CRISIS (c. AD 318–325)

Arius of Alexandria (c. AD 256–336)

Libyan by birth • trained at Antioch under Lucian • presbyter of the Baucalis church in Alexandria

PresbyterSubordinationistPopular teacher

Arius was a tall, ascetic presbyter of the Baucalis parish in Alexandria, widely admired as a preacher, a deft writer, and a singer. Around AD 318 he began to teach, with increasing boldness, that the Son of God is not co-eternal with the Father. His position ran roughly:

What Arius taught:

There is only one unoriginated God, the Father.
The Son is the first and highest of all creatures — but a creature, nonetheless, made before time began.
Therefore there was when he was not (Greek: ἦν ποτὲ ὅτε οὐκ ἦν, ēn pote hote ouk ēn) — the slogan of the Arian party.
The Son is not of the same substance as the Father; he is “from non-being” (ex ouk ontôn).
He is capable, in principle, of moral change; he is perfect by grace and by the Father’s will, not by nature.

Arius took his message straight to the people. He wrote a book called Thalia (“the Banquet”) in popular metre, set key lines to catchy tunes, and taught dockworkers and bakers to sing them. Athanasius tells us the ditties spread faster than his refutations. Arius’ most important Old Testament proof-text was the Septuagint of Proverbs 8:22, where personified Wisdom says:

LXX (Prov 8:22): κύριος ἔκτισέν με ἀρχὴν ὁδῶν αὐτοῦ εἰς ἔργα αὐτοῦ. Proverbs 8:22 (LXX): “The Lord created me (ektisen me) as the beginning of his ways for his works.”

Arius read this as proof that Wisdom (identified by a long patristic tradition with Christ) was created. The orthodox reply was either (a) that Proverbs 8 is not after all a direct prophecy of the eternal Son, or (b) that ektisen here is poetic for the Incarnation, not the Son’s eternal being. The verse would be argued for decades.

Bishop Alexander’s response. Around 318 Bishop Alexander of Alexandria summoned Arius to explain himself, then convened a local synod of Egyptian bishops that excommunicated him. Arius appealed to his friends in the East — above all Eusebius of Nicomedia, a former classmate from Lucian’s school and now a politically powerful bishop at Constantine’s capital. The controversy spilled out of Egypt and threatened to tear the empire’s newly unified church apart. Constantine, who understood churches better than he understood theology, sent a famous letter urging Alexander and Arius to stop arguing about what he called a “small and unimportant” theological point (Eusebius, Life of Constantine 2.68–71). The letter had no effect. By early 325 Constantine realized he would have to summon the bishops himself.

PART 3 — THE COUNCIL (MAY–JULY AD 325)

Constantine called the bishops to Nicaea (modern İznik), a pleasant lakeside town near the imperial summer capital of Nicomedia, reachable by sea and by the Roman roads. He paid their travel and accommodation from the imperial purse. The council opened in May or June 325 and sat for roughly eight weeks.

Attendance. The traditional count is 318 bishops — a number memorable because it matches the size of Abraham’s household army in Genesis 14:14. Modern scholars think the real number was somewhere between 250 and 300. Only seven or so were from the Latin West; the East dominated. Constantine himself opened the proceedings in a purple robe, speaking in Latin (with a Greek interpreter). It was the first time a Roman emperor had publicly addressed a Christian assembly.

Three parties emerged:

The Arians

A small minority, perhaps 20 bishops at most, led by Eusebius of Nicomedia. They presented a formal Arian creed early in the proceedings. It was dramatically rejected — Eusebius of Caesarea says the bishops tore it in pieces and stamped on it.

The Orthodox

Led by Bishop Alexander of Alexandria, with his 20-year-old deacon and secretary Athanasius arguing brilliantly from the floor. Supported by the Western bishops (few but theologically precise) and by Hosius of Cordoba, Constantine’s personal advisor.

The Moderates

The overwhelming majority — including Eusebius of Caesarea, the historian — who distrusted both Arian extremism and the novel orthodox word homoousios, and wanted a scripturally worded compromise that could be signed by all.

The Emperor

Constantine wanted agreement above all else. But when the moderate party’s compromise wording proved capable of Arian interpretation, Constantine himself seems to have suggested the decisive word — homoousios, “of one substance” — precisely because Arius could not sign it.

The vote. When the final creed was presented, all but two of the bishops present signed it. Arius himself was not a voting bishop. Two Libyan bishops (Secundus of Ptolemais and Theonas of Marmarica) refused to sign and were exiled with Arius. Eusebius of Nicomedia and Theognis of Nicaea signed the creed but refused to sign the anathemas appended to it; three months later they too were exiled.

Other business. Beyond the creed, Nicaea also: (1) standardized the date of Easter — the first Sunday after the first full moon following the vernal equinox, independent of the Jewish calendar, to be calculated by Alexandria and announced by Rome; (2) healed the Meletian schism in Egypt with lenient terms; (3) issued twenty canons of church discipline dealing with clerical conduct, readmission of the lapsed, and the rights of sees; (4) recognized a special honor for the sees of Rome, Alexandria, and Antioch — the seed of the later Pentarchy (see Lesson 2 Part 1).

PART 4 — THE NICENE CREED & HOMOOUSIOS

The text adopted at Nicaea is not quite the “Nicene Creed” we recite in church today — our version is the expanded form finalized at the Council of Constantinople in 381 (see Part 6). The original 325 text reads:

The Creed of Nicaea (325)

We believe in one God, the Father Almighty, Maker of all things visible and invisible.

And in one Lord Jesus Christ, the Son of God, begotten of the Father the only-begotten, that is, of the essence of the Father (ek tês ousias tou Patros), God of God, Light of Light, true God of true God, begotten, not made, being of one substance with the Father (homoousion tôi Patri), by whom all things were made both in heaven and on earth;

who for us men and for our salvation came down and was incarnate, was made man, suffered, and rose on the third day, ascended into the heavens, and will come to judge the living and the dead.

And in the Holy Spirit.

To the creed the council appended a set of anathemas explicitly ruling out every Arian formula:

“But those who say: ‘There was when he was not,’ or ‘Before he was begotten he was not,’ or ‘He was made out of nothing,’ or assert that the Son of God is of another essence (hypostasis or ousia), or is created, or changeable, or alterable — these the holy, catholic, and apostolic church anathematizes.”

The decisive word: homoousios.

ὁμοούσιος (homoousios) means “of the same substance.” It combines homos (“same”) with ousia (“being,” “substance,” “essence”).

The word was not in the Bible. That was the problem. It was also the solution: Arians could happily sign any purely scriptural formula because they read the Bible in a way that made the Son a creature. Only a non-biblical word — chosen precisely for its incompatibility with Arianism — could exclude them.

The orthodox gamble paid off. Homoousios became the one-word summary of what the church believes: the Son is everything the Father is, except that he is the Son and not the Father.

Why this was so important. The debate looked like it was about a Greek syllable. It was really about salvation.

• If the Son is a creature, then on the cross a very high creature died for us. A creature cannot save. Only God can join the human race to himself; only God can defeat death; only God can be worshipped without idolatry. Arian Christianity was a kind of elaborate monotheistic polytheism: God the Father worshipped, and a very exalted second being — not God — also worshipped alongside him.

• If the Son is homoousios, then God himself became one of us, died on the cross, and rose. The Incarnation is real; the atonement is God’s own self-gift; the Son we worship is no idol.

Athanasius later summarized the soteriological stakes in one famous line:

“He became what we are that he might make us what he is.”— Athanasius, On the Incarnation 54

PART 5 — ATHANASIUS CONTRA MUNDUM (AD 328–373)

Athanasius of Alexandria (c. AD 296–373)

Deacon at Nicaea at 20 • Bishop of Alexandria from 328 • exiled five times over 45 years • “Athanasius against the world”

Bishop of AlexandriaPro-NiceneExiled 5xOn the Incarnation

Nicaea had spoken, but the fight had only just begun. Constantine himself grew weary of his own decree; Arius was partially rehabilitated within two years. Constantine’s son Constantius II (r. 337–361) openly favored the Arian party. For most of the fifty-six years between Nicaea (325) and Constantinople (381), the imperial court was either Arian or Arianizing. The Nicene faith survived because one man refused to let it die: Athanasius of Alexandria.

He had been Alexander’s young secretary at Nicaea. In 328 he succeeded Alexander as Bishop of Alexandria at roughly 33. Within five years the Arian party had him condemned at a pro-Arian synod and exiled by Constantine. He would be exiled five times over the next forty-five years, spending a total of seventeen years away from his see — once hiding in the Egyptian desert with the monks of Anthony, once taking refuge with Julius of Rome.

The Latin phrase Athanasius contra mundum — “Athanasius against the world” — is a later summary but it captures what happened. At the nadir of the controversy, when councils in the West (Ariminum, 359) and the East (Seleucia, 359) both accepted Arianizing creeds, Jerome wrote famously: “The world groaned and marvelled to find itself Arian.” Athanasius, and a few others with him, kept preaching homoousios anyway.

“Our faith is neither from men nor by men, but from the Lord Jesus Christ, confessed by the fathers gathered at Nicaea.”— Athanasius, Letter to the Bishops of Africa 2

His major works:

• On the Incarnation (c. 318, before Nicaea) — a short masterpiece on why God’s Son had to become flesh. Still in print, still widely read, still unsurpassed as an introduction to classic Christology.

• Orations Against the Arians (c. 340s) — four books of detailed biblical and theological response.

• Life of Anthony (c. 360) — the biography of the desert father Anthony of Egypt; invented the genre of Christian hagiography and launched monastic biography as a literary form.

• Festal Letter 39 (367) — contains the first list of the 27 New Testament books exactly as we have them today. (See Lesson 1 Part 6.)

Athanasius outlived every emperor who had exiled him. He died peacefully in Alexandria in 373, eight years before the Council of Constantinople vindicated everything he had fought for.

PART 6 — THE FIFTY-SIX YEARS TO CONSTANTINOPLE (325–381)

Between Nicaea and Constantinople the controversy produced roughly thirteen major councils, a dozen competing creeds, five exiles of Athanasius, and the first serious murder of Christians by other Christians on imperial orders. The best short map:

• AD 337 — Constantine’s death. Having delayed his baptism all his life (as was common), he was finally baptized on his deathbed — by Eusebius of Nicomedia, an Arian. The empire was divided among his three sons.

• AD 337–361 — Constantius II. Constantine’s son, who eventually controlled the whole empire, was openly pro-Arian. He summoned council after council to find a formula the Arians could sign. Athanasius spent most of Constantius’ reign in exile or in hiding.

• AD 359 — The twin councils of Ariminum (West) and Seleucia (East). Under heavy imperial pressure, both councils were bullied into signing an Arianizing creed omitting homoousios. This is the moment Jerome describes as the world becoming Arian.

• c. AD 362–379 — The Cappadocian Fathers. Three brilliant theologians from Cappadocia (central Turkey) — Basil the Great, his brother Gregory of Nyssa, and their friend Gregory of Nazianzus — rework Nicene theology with a sharper distinction between ousia (substance, shared by the three) and hypostasis (person, distinct of each). This is the vocabulary that will finally settle the matter.

• AD 379 — Theodosius becomes emperor. Theodosius I, a Spaniard and a pro-Nicene, immediately makes Nicene Christianity the official faith of the empire (Edict of Thessalonica, 380).

• AD 381 — The First Council of Constantinople. Theodosius summons about 150 Eastern bishops to Constantinople. Under Gregory of Nazianzus (briefly) and then Nectarius, the council reaffirms Nicaea, expands its third article (“And in the Holy Spirit…” becomes the full pneumatological paragraph we still recite), and anathematizes the Macedonian heresy which had denied the Spirit’s divinity. The creed as revised is the Nicene-Constantinopolitan Creed we recite on Sundays.

With Constantinople 381, the Arian controversy was settled within the empire. It persisted in the Germanic kingdoms outside the empire (Goths, Vandals, Lombards) for two more centuries — partly because Ulfilas, the missionary bishop who evangelized the Goths and translated the Bible into Gothic, had himself been an Arian. By the late 6th century, Arian kingdoms had nearly all converted to Catholic Christianity.

PART 7 — WHY NOLL CALLS THIS A TURNING POINT

Noll gives this chapter the title Realities of Empire because Nicaea changed the church on two levels at once.

• Theologically: Nicaea is the first empire-wide binding dogmatic decision of the Christian church. The question “is Jesus God?” was answered, with anathemas, in a form every subsequent Christian tradition has inherited. Catholics, Orthodox, mainline Protestants, and confessional evangelicals all still say homoousios on Sundays (in translation). Nicaea is the floor.

• Politically: Nicaea is the first act in what historians call Caesaropapism — the fusion of imperial and ecclesiastical authority that would define Byzantine Christianity for a millennium. Constantine summoned the council, paid for it, attended it, bullied it toward consensus. Later emperors did worse: Constantius exiled orthodox bishops; Valens hunted them. The church got the space to think together — and lost the independence it had paid for in martyr’s blood for three centuries. Both gains and costs are real.

Noll’s warning: every Christian generation faces some version of the Nicene trade-off. Freedom, resources, and a seat at the table are not free. The church that accepts them accepts, in some measure, the priorities of the table that is setting them. The right answer is not to refuse the table (the Anabaptists tried, with mixed results — see the coming Reformation lessons); it is to remember, every day, whose table it really is.

WHY THIS MATTERS FOR US

• When we say “Jesus is Lord,” we are saying what Nicaea said. The shortest Christian confession in the New Testament (Rom 10:9) — and the one we are about to say in the Great Thanksgiving or the benediction — rests on the claim Arius denied: that the Son and the Father share the one divine nature. Cut the Nicene root and every other branch of Christian confession withers.

• Creeds are not the opposite of faith; they are its speakable form. “No creed but Christ” is a popular American slogan. But the Nicene Creed is the shape of a faith that can say what Christ is. The question is not whether we have a creed but whether ours is public and tested or private and untested.

• One stubborn bishop can save a century. Athanasius was exiled five times and never recanted. His faithfulness is a reminder that the Lord is not bound by democratic theology: he can preserve his truth through a single unbroken witness for as long as he needs to.

• The temptation of empire is still here. Every time the church reaches for political muscle to do what only the Holy Spirit can do, we are replaying a version of Nicaea’s shadow side. Political power is not always a gift.

Greek NT (John 10:30): ἐγὼ καὶ ὁ πατὴρ ἕν ἐσμεν. John 10:30 (ESV): “I and the Father are one.”

DISCUSSION QUESTIONS

1. Arius’ slogan was “there was when he was not.” What is at stake — for salvation, for worship, for the cross — if that slogan were true?

2. Homoousios was not a biblical word. The church chose it anyway. Is that a problem — or a feature? When is it right to use a non-biblical word to protect a biblical truth?

3. Constantine’s summoning of the council saved orthodoxy and also entangled it. Reading the story now, would you rather have lived in the pre-Constantinian church or the post-Constantinian one?

4. Athanasius was “against the world” for decades. Where in our own day do you see Christians being pressured to give up a doctrine because the culture (or the empire) has moved on?

5. Nicaea decided the date of Easter and healed a schism as well as settling doctrine. What does that mixture of dogmatic, pastoral, and practical business tell us about how councils actually function?

6. Read the Nicene Creed aloud in your group. Which line costs us the most, culturally, to keep confessing today?

CLOSING PRAYER

Lord Jesus Christ, homoousios with the Father, God of God, Light of Light, true God of true God, we thank you for Nicaea. Thank you for the bishops who came on crutches and remembered the arena. Thank you for Alexander and Athanasius and Hosius and the seven Westerners. Thank you for Constantine’s flawed, imperfect, decisive gathering of your servants. Thank you for the one word homoousios that kept your people from worshipping an idol. Forgive us for the moments when we reach for the emperor’s power instead of yours. Give us Athanasius’ steel and Basil’s clarity and the Cappadocians’ patience. Let us say the creed tomorrow morning as the church has said it for seventeen centuries — meaning every word. Amen.